optional
Americanadjective
-
left to one's choice; not required or mandatory.
Formal dress is optional.
- Synonyms:
- voluntary, elective, discretional
-
leaving something to choice.
adjective
Other Word Forms
Etymology
Origin of optional
Explanation
If you can choose whether or not to do something, it is optional. Extra credit is always optional; death and taxes are not. When you buy a new car, you can decide which options or choices, you would like. Things like a DVD player mounted in the ceiling are optional, you don't need them for the car to work, and it's up to you if you want to pay more for them. The opposite of optional is mandatory. If you're in high school, going to bed at 8:00 is optional, for your little sister in elementary school, it's mandatory.
Vocabulary lists containing optional
Jim Burke's Academic Vocabulary List
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100 SAT words Beginning with "O"
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New Kid
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
After Sony reported those numbers, rumors began circulating that the upcoming PS6 will be totally disc-free, making the Blu-ray reader a separately sold, optional piece of hardware.
From Slate • Jul. 7, 2026
This comes after Defense Secretary Pete Hegseth made the shots optional in late April.
From Salon • Jun. 30, 2026
“This is not optional, it is mandatory for the U.S. to maintain a leadership position in space.”
From MarketWatch • Jun. 25, 2026
The optional fee package will cost around $550 for a semester, depending on the number of course credits.
From The Wall Street Journal • Jun. 11, 2026
"Willow, you've been ordered to come here for behavioral reasons. It's not optional."
From "Counting by 7s" by Holly Goldberg Sloan
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
